1. Field of the Invention
The present invention relates to communications over networks and, more particularly, to management of network resources for improved communications over networks.
2. Description of the Related Art
A communications network includes links or transmission media, data storage, and servers, all of which serve as resources of the communications network. When these resources become overloaded, the communications network does not operate properly and performance rapidly deteriorates. Thus, it is desirable to not overload the resources of the communications network.
An electronic mail system is a particular type of communications network. Typically, an electronic mail system has a local network over which user machines (computers) are interconnected. An example of a local network is a Local Area Network (LAN) that interconnects user machines located proximate to one another. Normally, one machine coupled to the local network is referred to as a mail server. The mail server operates to manage and administer the distribution and reception of mail messages to/from the various user machines.
An electronic mail system may also have access to a global network known as the Internet. Normally, the electronic mail system can couple to the Internet via an Internet service provider (ISP). Each ISP services a large number of different mail servers. The ISP has limited resources to handle all the incoming requests to transmit and receive electronic mail messages from the different mail servers being serviced. In a typical setup for smaller scale local area networks (LANs), the ISP is remotely located from the different the mail servers and the Internet. A mail server connects to the ISP over phone lines when initiated by the mail server. The ISP, on the other hand, is connected to the Internet over a high-bandwidth link known as a leased line. Hence, to obtain global electronic mail service, the mail server connects to the ISP as needed or requested. Once the mail server is connected with the ISP, the mail server is able to send and receive electronic mail messages over the Internet. The connection of the mail server to the ISP is normally done at predetermined connection times that have be set by a system administrator.
Generally, the connection to the ISP is a fee-based service. As a result, to reduce expenses, it is desirable in most cases to limit the frequency at which the connections to the ISP are made as well as the duration of the connections. However, if the frequency at which the connections are made is too infrequent, the performance of the electronic mail system suffers. The duration of the connections is normally the length of time needed to send and receive all the electronic mail messages between the mail server and the ISP. In any case, the system administrator determines when the connections are to be made. In a typical electronic mail system, when installing and configuring the software on the mail server, the system administrator will select the connection times. For example, in an electronic mail system known as QuickMail, produced by CE Software, Inc. of West Des Monies, Iowa, the system administrator is presented with a dialog screen where the connect times are selected. With QuickMail, the system administrator can set the electronic mail system to connect: when at least x number of messages are waiting; when at least y number of urgent messages are waiting; and/or every z minutes between certain hours of certain days in a week. With QuickMail, the system administrator can also restrict the system to connect only once per day.
One significant problem with conventional mail systems is that the loading of the ISP's resources is overloaded. In particular, during peak usage hours, a large number of the electronic mail systems in existence will likely desire connection to their ISP so that they may send and receive mail through the Internet. However, it is burdensome for an ISP to have to service all of its electronic mail system subscribers at the same time. It is burdensome because the ISP would have to buy hardware and provide resources for the worst case scenario, namely, servicing all of its electronic mail system subscribers at the same time. Given the competitive nature of the ISP business, it is also cost prohibitive for an ISP to provide hardware and resources for the worst case scenario. For this reason, many ISPs cannot concurrently handle connections from a large number of its electronic mail systems subscribers. When a large number of connections are needed (e.g., during periods of peak utilization), the ISP resources are overloaded and performance is poor or unavailable to many of its electronic mail systems subscribers.
Thus, there is a need for techniques that allow an ISP to better manage its resources so that its performance is more predictable and more manageable.